1. Field
The described technology relates generally to a substrate cutting apparatus and a substrate cutting method thereof. More particularly, the described technology relates generally to a substrate cutting apparatus with a laser beam capable of stably and effectively cutting a glass substrate, and a substrate cutting method using the same.
2. Description of the Related Art
A flat panel display may include an organic light emitting diode (OLED) display and a liquid crystal display (LCD). The flat panel display may be thin, so a substrate cutting apparatus may be required to cut a thin substrate for the thin flat panel display into a desired size.
A conventional substrate cutting apparatus may include a CO2 laser, i.e., as an infrared-base laser for cutting a transparent glass substrate, and a cooling means. That is, the conventional substrate cutting apparatus may apply heat to the substrate along a cutting line by using a CO2 gas laser to generate compression stress. Then, the conventional substrate cutting apparatus may cool the heated portion with the cooling means to generate tensile stress. When this heating/cooling impact, i.e., temperature difference, is applied to the substrate, a minute micro-crack may be generated to facilitate cutting of the substrate.
However, it may be difficult to smoothly generate micro-cracks by stress caused by a temperature difference as the thickness of the substrate is reduced. Therefore, it may be difficult to cut a thin substrate, e.g., just as a thin glass cup may not be easily broken in hot water.
The above information disclosed in this Description of the Related Art section is only for enhancement of understanding of the background of the described technology and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.